The known techniques of hair removal include electrolysis and various laser hair removal techniques and skin treatments. Laser hair removal is described in United States patents to Weissman et al., U.S. Pat. No. 4,388,924; Sutton, U.S. Pat. No. 4,617,926; Mayer, U.S. Pat. No. 3,538,919; and Zaias, U.S. Pat. No. 5,059,192.
It is also known to effect long-term inhibition of hair growth by infiltrating a light-absorbing contaminant into hair ducts in a skin section prior to laser treatment. This technique is described in U.S. Pat. Nos. 5,226,907 and 5,425,728 to Tankovich. A contaminant applied topically can also be used to facilitate laser skin resurfacing. The contaminant is infiltrated beneath the surface layers of the stratum corneum, and then the skin surface bearing the contaminant is illuminated so as to remove the surface layers of the stratum corneum. This technique is described in U.S. Pat. No. 5,423,803 to Tankovich.
Accordingly, after noting the limitations of the prior art techniques, the inventors of the present application have devised new methods and devices used in long term prevention of hair growth and other beneficial skin treatments.